Method for providing information services in characters through ISDN

ABSTRACT

A method for providing information services to display the character information on terminals by a PBX through an ISDN, the method comprising the steps of registering a subscriber&#39;s request of character information services according to a given menu by connecting a specified port to the ISDN, determining whether corresponding terminal is registered for the character information services upon receiving a service message, and transferring the service message to be displayed in characters on the registered terminal.

CLAIM OF PRIORITY

This application makes reference to, incorporates the same herein, andclaims all benefits accruing under 35 U.S.C. Section 119 from anapplication for METHOD OF PROVIDING INFORMATION SERVICES IN CHARACTERTHROUGH ISDN filed earlier in the Korean Industrial Property Office onthe 24th day of Dec. 1998 and there duly assigned Ser. No. 58361/1995.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for providing informationservices in the form of characters by PBX (Private Branch Exchange)through ISDN (Integrated Services Digital Network).

2. Description of the Related Art

The ISDN is a network designed to bring the features of PBX systems andhigh speed data-transfer capability to the standard telephone system toprovide a wide variety of digital services to subscribers. These manyavailable services include digital voice telephone, interactiveinformation, fax, electronic mail, and wideband digital video services.Before the ISDN can be fully implemented, digital channels must beestablished to all end users, and the channels must be able to handle avariety of services with different bandwidth requirements and datarates. To this end, a standard interface must exist for all subscribers.

The ISDN interface usually includes “2B+D” multiplex system having twovoice channels, the “B” channel which carries the customer'scommunication with the transmission speed of 64kbit/sec, and the “D”channel which provides control and signaling for the “B” channels with atransmission speed of 16 kbit/sec. The transmission speed of 64kbit/secin the B-channel corresponds to a voice signal of a standard telephonethat is modulated by the pulse code (PCM) according to the CCITTstandard. The D-channel may be used to transmit control signals or datapackets. For example, the control signals may be a sending signal and adial signal being transferred from a telephone to a switching system anda call signal representing the sender's number and communication requestdata from a switching system to a telephone.

The foregoing various control signals are transmitted as data packetsthrough D-channel. In addition, user-user information (UUI) data whichis one of the messages as defined by the International StandardOrganization (ISO) may be transmitted through D-channel to exchangeshort management message to be displayed on the terminals. Currently,the conventional communication system for the ISDN only provides voiceor data communication services through B-channel, and not throughD-channel.

SUMMARY OF THE INVENTION

It is one object of the present invention to provide a method forproviding information services to display character information on theterminals by PBX through Integrated Services Digital Network (ISDN)services.

According to one embodiment of the present invention, there is provideda method for providing information services to display characterinformation on terminals by the PBX through the ISDN services, themethod comprising the steps of registering a subscriber's request ofcharacter information services according to a given menu by connecting aspecified port to the ISDN, determining whether the correspondingterminal is registered for the character information services uponreceiving a service message therefrom, and transferring the servicemessage to be displayed in characters on the registered terminal.

According to another embodiment of the present invention, there isprovided a method for providing information services to displaycharacter information on terminals by the PBX through the ISDN services,the method comprising the steps of transmitting a service message to asubscriber from the ISDN periodically; determining whether the servicemessage is said character information; and, outputting the servicemessage on a display unit of the terminal if the service message is thecharacter information.

Another embodiment of the present invention provides a step forconnecting the terminal with a specified port of the ISDN if the servicemessage is not the character information.

Further embodiment of the present invention provides a step fordetermining whether the terminal is registered for the characterinformation service if the service message is character information, andoutputting the service message on the display unit of the terminal inresponse to a determination that the terminal is registered for thecharacter information service.

Preferably, the message is UUI adapted according to the ISDN protocolfor the character information service, and the message is transmittedthrough D-channel of the ISDN.

The foregoing and other objects, features, and advantages of theinvention will be apparent from the following more particulardescription of preferred embodiments as illustrated in the accompanyingdrawings in which reference characters refer to the same partsthroughout the various views. The drawings are not necessarily to scale,emphasis instead being placed upon illustrating the principles of theinvention.

A BRIEF DESCRIPTION OF THE ATTACHED DRAWINGS

FIG. 1 is a schematic diagram for illustrating a general communicationnetwork to which the present invention is applied;

FIG. 2 is a block diagram for illustrating the conventional structure ofa PBX according to an embodiment of the present invention;

FIG. 3 is a flow chart for illustrating the process for registeringservice in order to provide character information services through a PBXaccording to an embodiment of the present invention;

FIG. 4 is a flow chart for illustrating the process of transmittingcharacter information via D-channel; and,

FIG. 5 is a block diagram for illustrating the conventional structure ofa PBX as a service provider according to another embodiment of thepresent invention.

A DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a PBX 120 is connected to an ISDN 110 to provideinformation services to a plurality of subscribers 130_a to 130_d. Thefundamental structure of the PBX 120 for the present invention may haveexclusively or partly an ISDN office-line/extension circuit 230, asshown in FIG. 2.

Referring to FIG. 2, a CPU 210 is provided to control the operationalfunctions of the PBX and the function of providing character informationto a terminal through the ISDN service. The various signals of the PBXcomponents are switched to each other by a switch part 212. A memory 214stores the control program required for the CPU 210 and various datagenerated from the PBX. A tone generator 216 generates various tonesignals provided by the PBX, such as a busy tone, a sending tone, acalling tone, and other tones. A ring generator 218 generates the ringsignal that is supplied to the extensions of subscribers upon receivinga call request via the switching part 212. A DTMF (Dual ToneMulti-Frequency) receiver 220 analyzes a DTMF signal received throughthe switching circuit 212 and transmits to the CPU 210. A DTMFtransmitter 222 generates a DTMF signal applied to the switching part212. An ordinary subscriber circuit 224 interfaces the switching part212 with the extension of a subscriber. An office line circuit part 226includes an ordinary office line circuit and a DID interface tointerface with the switching part 212. A key phone subscriber circuit228 interfaces the switching circuit 212 with the extension of a keyphone subscriber, and an ISDN circuit 230 interfaces the switching part212 with the ISDN.

FIG. 3 depicts a flow chart illustrating the process of registeringservices. The CPU 210 seizes a specified port of the ISDN to register aservice request to the terminal of a subscriber in order to provide thecharacter information service in response to a given selection in themenu feature of the terminal, determines whether the correspondingterminal is registered for the character information service uponreceiving a service message signal from the ISDN, and transfers theservice message to be displayed with characters on the terminal in theevent that that the terminal is registered.

FIG. 4 depicts a flow chart illustrating the process for generatingcharacter information via D-channel. When the system is in idle state, aservice message is transmitted to the subscriber from the ISDNperiodically, thus in step 412, the CPU 210 in idle state checks forwhether any character information is received from the ISDN as set bythe operator. In step 414, if any service message is received, the CPU210 checks whether the received service message is character informationmessage. At step 426, if the received service message is characterinformation message, the character information message is directlyoutputted on the display unit of the terminal. However, if the servicemessage is not character information message, namely registrationinformation, in step 414, a message registration procedure is performedaccording to the procedure including steps 314, 316, 318, and 320 ofFIG. 3.

Meanwhile, if the service message is not received in step 412, the CPU210 checks whether B-channel connection message is received from theISDN in step 416. If the B-channel connection message is received instep 416, the CPU 210 connects the B-channel in step 418 and the channelis switched accordingly in step 420. However, if the B-channel is notreceived—for example, if the B-channel is already been connected—the CPU210 checks whether the B-channel release message is received in step422. If the B-channel release message is received, the B-channel isreleased in step 424. If the B-channel release message is not received,the terminal of the subscriber goes into idle state.

The PBX, as a service provider for providing character informationservices is shown in FIG. 5, where the information source may consist ofa PC console, data communication line, internet line, etc., to providecharacter information in real time.

From this point, the process of providing character information throughthe ISDN service according to the present invention will be morespecifically described. The ISDN service employs out band signaling totransfer the call control information through the D-channel. Generally,the D-channel transmits control information during a process thatinvolves demanding, controlling and releasing a call. Otherwise, thechannel is in idle state in the other times.

According to the present invention, the character information service isperformed through the D-channel during an idle state. The process forregistering the contents of character information service may beaccomplished by direct communication with the operator of the PBX, oraccording to a given menu selection to initiate on-line registrationduring the on-line connection to the PBX. The on-line registration isachieved through steps 314 to 320, as shown in FIG. 3.

Referring to FIGS. 2 and 3, the CPU 210 repeats the loop from step 310to step 314 to detect whether the terminal requests for the characterinformation service. In step 312, service message is periodicallyreceived from the ISDN. In step 314, a user's specific request forsetting the character information service is checked. Thus, upondetecting the request for the character information service in step 314,the CPU 210 proceeds to step 316 to connect a specific port of the ISDNcapable of providing the character information service. The specificport has such functions as “auto announce”, “DB”, etc. Then, the CPU 210controls the switching part 212 to connect the terminal requesting thecharacter information service with the specific port of the ISDN.Furthermore, using a key pad, a voice message for the menu can betransmitted through the connected port to the subscriber of the terminalto input a desired input and/or other features of the services.

Accordingly, the CPU 210 receives a DTMF signal via the DTMF receiver220 to perform the registration of the service. The signal requestingfor character information service received from the terminal isconverted into digital form using the DTMF receiver, which is thentransferred to the CPU 210 via switching part 212. Upon completing theservice registration, the CPU 210 proceeds to step 320 to terminate thecall connecting process of the specific port of the ISDN, and theprocess returns to step 310.

Thereafter, the CPU 210 repeats the loop from step 310 and step 312 fordetection of the receipt of a service message. Upon receiving theservice message in step 312, the CPU 210 proceeds to step 322 to deliverthe character information to the corresponding terminal that waspreviously registered through step 314-320. Namely, whenever characterinformation is received through the D-channel, the CPU 210 transmits thecharacter information when the corresponding terminal is registered forsuch service. The terminal should have a display unit for displayingcharacter information. This, the character message transmitted throughthe D-channel should be adapted to the ISDN system meeting therequirements of the ISDN protocol. To this end, UUI message may be usedas set forth under ISO standard.

Upon completing the subscriber's registration of the characterinformation service, the CPU 210 of the PBX enables the characterinformation to be transmitted to a display unit provided in thesubscriber's ISDN terminal according to the registered information at aspecified time, when necessary or continuously. Further, the content ofthe character information service may be altered by deleting or addingduring the service or at any time as occasion demands.

In addition, if the service message received from the ISDN does notcontain character information, the voice message may be transmittedthrough B-channel as in the prior art, as shown in the step 416 and itssubsequent steps in FIG. 4.

Thus, the present inventive method provides the ISDN system withcharacter information services through the D-channel without having anyadditional hardware as well as the basic voice and data communicationservices through the B-channels, thereby improving the utility of ISDN.

While the preferred embodiments of the present invention have beenillustrated and described, it will be understood by those skilled in theart that various changes and modifications may be made, and equivalentsmay be substituted for elements thereof without departing from the truescope of the present invention. In addition, many modifications may bemade to adapt to a particular situation to the teaching of the presentinvention without departing from the central scope thereof. Therefore,it is intended that the present invention not be limited to theparticular embodiment disclosed as the best mode contemplated forcarrying out the present invention, but that the present inventionincludes all embodiments falling within the scope of the appendedclaims.

What is claimed is:
 1. A method for providing a character informationservice to display character information on a terminal by a privatebranch exchange (PBX) through an integrated services digital network(ISDN), said method comprising the steps of: registering a subscriber'srequest for said character information service during an idle state of achannel of said ISDN by connecting a terminal of said subscriber with aspecified port of said ISDN that is capable of providing said characterinformation service, and disconnecting from said terminal from thespecified port when registration has been completed; upon receiving ashort message containing said character information from said ISDN,determining whether said terminal is registered for said characterinformation service; and, transferring said service message containingsaid character information to be displayed in a display unit of saidregistered terminal.
 2. The method as defined in claim 1, wherein saidservice message uses user-user information (UUI) as set forth underInternational standard organization (ISO) to be adapted to said ISDNprotocol.
 3. The method as defined in claim 1, wherein said servicemessage is transmitted through D-channel of said ISDN.
 4. The methodaccording to claim 1, wherein the registering step is performed by usingan on-line selection menu.
 5. The method according to claim 1, whereinthe registering step is by direct communication between an operator ofthe PBX and the ISDN.
 6. A method for providing a character informationservice to display character information on a terminal by a privatebranch exchange (PBX) through an integrated services digital network(ISDN), said method comprising the steps of: transmitting a servicemessage to a subscriber from said ISDN periodically during an idle stateof an ISDN channel; determining whether said service message is saidcharacter information; in the event that said service message is saidcharacter information, outputting said service message on a display unitof said terminal; and, in the event that said service message is notsaid character information, connecting said terminal of said subscriberwith a specified port of said ISDN.
 7. The method as defined in claim 6,wherein said method further comprises the step of determining whethersaid terminal is registered for said character information service ifsaid service message is said character information.
 8. The method asdefined in claim 7, wherein said step of determining whether saidterminal is registered comprises the step of outputting said servicemessage on said display unit of said terminal in response to adetermination that said terminal is registered for said characterinformation service.
 9. The method as defined in claim 6, wherein saidservice message uses user-user information (UT) as set forth underInternational standard organization (ISO) to be adapted to said ISDNprotocol.
 10. The method as defined in claim 6, wherein said servicemessage is transmitted through D-channel of said ISDN.